Water storage tank

ABSTRACT

A water storage tank is formed by a plurality of curved wall sections adapted to be secured together to form a circular tank. A ground mat is placed on the ground and extends outwardly of the tank wall. A plurality of hold down members are placed at the inside juncture of the tank wall and ground mat. A flooring sheet overlaps the ground mat and extends up and over the side wall of the tank and is clamped to an upper portion of the wall. A tubular fitting extends through a lower portion of the side wall to provide an inlet and outlet for water.

BACKGROUND OF INVENTION

1. Field of the Invention

This invention relates to a water storage tank that can be assembled ona work site where there is a need for storing water. Also disclosed is aplurality of subcombinations that can be used in conjunction with knownwater storage tanks including a hydraulic hold down, a spout, a clamp,and wall joint structure as more fully disclosed herein.

2. Description of Related Art

In the oil and gas industry, water storage has become an issue due tothe large amount of barrels of water required to perform drillingoperations. Cost of transporting a large number of tanks to location,and logistical problems of having enough space at the well site toaccommodate their positioning has forced the oil and gas industry tofind a solution. The solution that has developed is the use of a singlemobile erecting tank. These tanks eliminate a large fleet of storagevessels and the cost of transporting them to location.

These large capacity tanks normally comprise 16 single panels thatconnect together side by side, forming in one embodiment a 122 ft.diameter tank with a height of 12 ft. After they are assembled a rubbersheet, plastic, or polypropylene sheet is positioned in the inside andthe edges are laid over the top rail of the tank. These edges of thesheet are secured to the top rail by the use of c-clamps.

The suction lines are then hung over into the tank and the tank is thenfilled with water. As the tank is filled, water forces the sheet intothe lower inside corners of the tank. This can allow the sheet to bepinched or protrude under the wall of the tank causing a leak or tear ofthe rubber sheet.

BRIEF SUMMARY OF THE INVENTION

The present invention employs a first ground cover mat that ispositioned on the ground. The mat is circular in shape and extendsbeyond the wall sections of the tank which are placed on top of the matto form a circular wall. A second mat may then be positioned on top ofthe ground mat within the area of the walls. A plurality of arcuatehydraulic hold downs are positioned at the junction of the tank wall andsecond mat around the entire interior of the tank. The hold down helpsstabilize the side and provides for a protection device that preventsthe rubberized sheet from protruding under the tank wall and notallowing the rubber to be exposed to a sharp ninety degree corner.

A novel spout assembly is also disclosed so as to enable water or otherfluids to be pumped into and out of the tanks

Finally, a novel clamping mechanism has been developed to clamp thefinal sheet of material over the top portion of the circular wall of thetank.

While this discussion of a summary of the invention has been provided,it is understood that the invention of the present invention is definedby the claims included at the end of this specification.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

FIG. 1 is a perspective view of a wall section of the water tank.

FIG. 2 is a perspective view of a water tank formed by a plurality ofthe wall sections shown in FIG. 1.

FIG. 3 is a perspective view of a hydraulic hold down according to anembodiment of the invention.

FIG. 4 is a view taken along line A-A of FIG. 3.

FIG. 5 is a cross-sectional view of the tank wall and bottom structure.

FIG. 6 is a perspective view of a clamp according to an embodiment ofthe invention.

FIG. 7 is a cross-sectional view taken along line 6-6 of FIG. 6.

FIG. 8 is a perspective view of a spout according to an embodiment ofthe invention.

FIG. 9 is a side view of the spout.

FIG. 10 is a cross-sectional view of the spout attached to a wallsection of the tank.

FIG. 11 is a front view of one of the split rings shown in FIG. 10.

FIG. 12 is a front view of a keeper ring as shown in FIG. 10.

FIG. 13 is a cross-sectional view taken along line 13-13 of FIG. 12.

DETAILED DESCRIPTION OF THE INVENTION

An embodiment of the invention will now be discussed with reference tothe figures. As shown in FIG. 2, a circular wall forming the storagetank 1 is formed by a plurality of individual curved wall sections 30 asillustrated in FIG. 1. Each wall section 30 includes a frame formed by atop 31, a bottom 32, vertical members 33 and thin walled portions 34.One end of the wall section 30 includes a vertically extending plate 36having apertures 37 therein and the opposite end of the wall section hasa vertically extending plate 38 having a plurality of pins on 39 thatare adapted to extend through the apertures 37.

Pins 39 may be secured within apertures 37 by a suitable fasteningdevice such as a pin extending through a bore in pins 39. Also a sealinggasket 12 may be placed over the vertically extending joint to preventthe final layer from being forced into the joint as will be describedbelow.

Channels 51 may be formed in the ground within the area defined by thecircular wall to provide a drainage ditch.

Prior to the wall sections being placed on the ground 101, a circularground mat of flexible water impermeable material 2 is positioned overthe ground which has been leveled and cleared of debris to the extentnecessary as shown in FIG. 5. Ground mat 2 extends a given distanceoutwardly from the circular wall 4, for example two feet. This forms aprotective barrier preventing damage to the final cover and prevents theground from getting saturated which could cause a catastrophic failureof the grown under the tank. The mat 2 may be of any suitable thicknessfor example forty four mm and may be a polypropylene web reinforcedsheet. The diameter of the sheet is selected to be slightly larger thanthe diameter of the tank, for example, the ground mat may extend adistance of 1-5 feet beyond the tank wall as shown in FIG. 5.

A protective mat 3, which can be made of felt, polypropylene, rubber, orvarious types of padding, may be laid on top of ground mat 2 within thewall of the tank as shown in FIG. 5. This adds an additional layer ofprotection from sharp objects that may come into contact with groundlayer 2.

FIGS. 3 and 4 illustrate a novel hydraulic hold down according to anembodiment of the invention. A hydraulic hold down device 47 is formedwith a horizontally extending planar portion 41, a ninety degree bendportion 44 and vertically extending portion 42. Extending along andattached to the bend portion 44 is an L-shaped reinforcing bar.Hydraulic hold downs 47 have a curvature that corresponds to thecurvature of wall sections 30 so that they conform to the interface ofwalls 4 with protective mat 3 as shown in FIG. 5. A plurality of thehydraulic hold downs are placed within the tank so as to form a completecircle. The curvature of the hold downs is selected so as to form acircle having a diameter that corresponds to the diameter of the tank.

By way of example, horizontal portion 41 may be about twelve inches inwidth and portion 42 may be two inches in height. The hydraulic holddowns also help to stabilize the side walls.

Once the hold downs have been placed around the entire inner peripheryof the tank wall, a protective strip 5 of material which may be felt,rubber, polypropylene, or any other protective material is placed on topof the hydraulic hold downs as shown in FIG. 5. The strip extendsslightly beyond the horizontal and vertical portions of the hydraulichold down as shown in FIG. 5 so as to cover any sharp edges on thehydraulic hold downs.

The next step in constructing the water tank is to position a flexible,circular floor sheet over the wall assembly so that it will cover theground within the tank wall and extend upwardly and over the top portionof the tank wall as shown in FIG. 5. Circular floor sheet 8 will coverprotective strip 5 and hold downs 47 and will form a fluid tight tankwhich includes side walls sections 30 and ground mat 2. A suitable clampwhich may be any known type of clamp is used to clamp the upper portionof the floor sheet 8 to the upper wall portion 9 as shown in FIG. 5. Aclamping mechanism has been developed to clamp the upper portion ofsheet 8 to the upper portion of side walls 30. As shown in FIGS. 6 and7, the clamp 60 includes two relatively thin strips 61 and 62 offlexible material such as sheet metal or plastic. Strips 61 and 62 areslightly curved to conform to the curvature of wall portions 30 and arespaced apart by one or more spacers 63 at the top portion of each strip.Spacers 63 are welded or otherwise secured to strips 61 and 62, and maybe V-shaped.

A plurality of threaded bolts 64 extend through apertures formed instrips 61 and 62 at a position below where the spacers are located. Nuts65 are positioned on each end of threaded bolts 64. As the nuts arethreaded inwardly, they will engage strips 61 and 62 which will causethe strips to flex inwardly and thus clamp sheet 8 to the upper portionof wall 8 when the clamps are positioned as shown in FIG. 5. Althoughtwo nuts are shown in FIG. 7, the clamp could include only one nut oneither end of the rod or bolt 64.

Clamps 60 may be spaced around the top of tank wall 4 or they maycompletely cover the top portion of the wall.

As shown in FIG. 10, a tubular fitting 70 is located in a side wall ofthe tank for easy filling and draining of the tank as needed. This isaccomplished by the provision of a fitting for attachment to a fluidconduit for supplying or withdrawing water to and from the tanks Asshown in FIGS. 8 and 9, tubular fitting 70 includes generally hollowcylindrical body portions 76, 74 and 72 with a beveled portion 73between 72 and 74. A circular flange 71 is located on an exterior end ofthe fitting. Fitting 70 is placed through an aperture located in a lowerportion of a wall section as shown in FIG. 10. Fitting 70 also includesan annular groove 75 between flange 71 and body portion 72. Suitablethreads 95 may be provided on the outside surface of body portion 74 forconnection to a water conduit.

In order to form a water tight seal, a rubber seal 79 is positionedbetween the flange 4 and the inside surface of tank 4. The rubber sealmay consist of the portion of the floor sheet that extends upwardlyalong the inner tank wall or may be a separate circular ring member. Awall stiffening ring 99 is welded to the outside surface of the wall.Next a pair of split rings as shown in FIG. 11 are positioned withingroove 75 and are held in place by a keeper ring 83 shown in FIGS. 12and 13. With the components positioned as shown in FIG. 10, the assemblyis bolted together by bolts 98 that extend up to wall stiffening ring99.

Rubber seal 79 may be a conventional circular seal.

Wall stiffening ring 99 is a circular washer of stiff material and has ahole diameter so that it sits on outer surface 76 of the fitting 70.

The keeper ring 80 is illustrated in FIGS. 12 and 13 and comprises anannular ring portion 81 having a plurality of apertures 82 formedtherein. The ring 80 also includes a longitudinally extending flange 83that extends at a right angle from ring portion 81. Keeper ring 80 alsohas a centrally located opening 84 so that the ring may fit over theoutside periphery of the tubular fitting.

A split ring is shown in FIG. 11 and includes an arcuate body portion 91and a plurality of threaded apertures 92.

Two split rings are placed within the groove 75 of fitting 70 as shownin FIG. 10

Although the present invention has been described with respect tospecific details, it is not intended that such details should beregarded as limitations on the scope of the invention, except to theextent that they are included in the accompanying claims.

I claim:
 1. A water storage tank that can be assembled at a remotelocation comprising: a plurality of curved wall sections adapted to beconnected together to form a circular wall of the tank; a ground matcovering the ground within the tank and extending outwardly from thewall a given distance; a plurality of hold down mechanisms positioned ontop of the ground mat having a first horizontal portion and a secondvertical portion extending upwardly along the wall of the tank; aflexible tank floor formed of sheet material overlying the ground matand extending upwardly and over an upper portion of the circular wall ofthe tank; and a plurality of clamps for clamping the flexible tank floorto the upper portion of the circular wall of the tank.
 2. A waterstorage tank according to claim 1 further including a tubular fittingextending through a lower portion of a wall section for providing fluidcommunication between the tank and a fluid conduit.
 3. A water storagetank according to claim 1 wherein the hold down mechanisms furtherinclude a curved section between the horizontal and vertical portions.4. A water storage tank according to claim 3 wherein the hold downmechanisms are curved in a horizontal plane to conform to the curvatureof the tank side wall.
 5. A water storage tank according to claim 1further including a protective mat positioned between the ground mat andthe flexible floor.
 6. A water storage tank as claimed in claim 1further comprises a strip of protective material overlying the hold downmechanisms to protect the flooring from corners of the hold downmechanisms.
 7. A water storage tank as claimed in claim 3 wherein thehold down mechanisms include a reinforcement L-shaped member extendingalong the curved portion of the hold down mechanism.